This invention relates to sampling devices and apparatus and more particularly to a device for enabling an operator to take a liquid sample for subsequent analyses without contacting the liquid or releasing it to the surrounding atmosphere.
Many liquids such as petroleum products and petro-chemicals which are stored and transported in various tanks or containers in commerce must be sampled upon various occasions as when being sold. Existing legal and contractural requirements necessitate sampling according to procedures specified in the American Society for Testing and Materials (ASTM) D270-65. A typical procedure according to these standards is the so-called running method wherein an unstopped beaker or bottle is lowered from above the top level of the liquid (in a tank car, for example) to the level of the bottom of the outlet connection or swing line, and returning it to the top of the liquid at a uniform rate of speed such that the beaker or bottle is about three-fourths full when withdrawn from the oil.
With the discovery of carcinogenic effects of many industrial feedstocks, as well as the increasing use of more obviously toxic or flammable chemicals, it became essential to reduce or prevent entirely any worker exposure to such liquids during a sampling procedure. Yet, the volume of such liquids being transported in commerce steadily increased.
A similar problem of operator exposure was encountered in the taking of liquid samples from pipelines or other conduits. Consequently, an urgent need arose to provide an adequate apparatus that would enable a relatively unskilled worker to accomplish accurate sampling of a body of liquid in a tank, vessel, pipeline, or other containment while minimizing operator exposure to the liquid. The present invention solves this problem.